Keyboard with interconnected keys

ABSTRACT

Integral keys including a finger piece, a connecting arm and a support arm are arranged in lines and column rows in a keyboard. The support arm of each key has a guide opening for guiding the connecting arm of the preceding key, and is located under the finger piece of the respective preceding key of the same column row. The supporting arms of all keys of several lines are mounted for angular movement with the finger pieces about parallel shafts.

United States Patent Heinz Ricke Braunschweig, Germany 880,230

Nov. 26, 1969 Apr. 13, 1971 Olympia Werke AG Wilhelmshaven, Germany lnventor Appl. No. Filed Patented Assignee KEYBOARD WITH INTERCONNECTED KEYS 16 Claims, 4 Drawing Figs.

US. Cl 235/145, 197/98 Int. Cl G06c 7/02, B4 1 j 5/08 Field of Search 235/145,

[5 6] References Cited UNITED STATES PATENTS 1,795,468 3/1931 Bonilla 84/423 3,356,296 12/1967 Wirth 235/27 Primary Examiner-Stephen J. Tomsky Attorney-Michael S. Striker ABSTRACT: lntegral keys including a finger piece, a connecting arm and a support arm are arranged in lines and column rows in a keyboard. The support arm of each key has a guide opening for guiding the connecting arm of the preceding key, and is located under the finger piece of the respective preceding key of the same column row. The supporting arms of all keys of several lines are mounted for angular movement with the finger pieces about parallel shafts.

KEYBOARD WITH INTERCONNECTED KEYS BACKGROUND OF THE INVENTION It is known to use keys having supporting lever arms and finger pieces in keyboards of business machines. The supporting lever arms are mounted on shafts so that the keys of successive lines have supporting lever arms of different length. Since the support on the respective shaft is insufficient to determine the' lateral position of each key, additional supporting guides are provided. The transfer of the key motion to elements operated by the same; takes place by connectors attached to the support lever, or by means of cams. The distance between the shaft supporting a key and the finger piece is greater than the distance between the shaft and the actuator portion of the key so that the stroke of the finger piece is greater than the stroke of the actuator portion.

It is also known to provide the keys with vertical key stems which are guided in two bearings. The assembly is difficult and time-consuming, and since the stroke of the key is vertically transmitted to the operated elements of the machine, an increase of the effective stroke as compared with the key stroke is only possible when additional levers are provided.

It is characteristic of the prior art that, in addition to pivotal support, guide means have to be provided for the keys so that their assembly is difficult, the noise of the key operations is substantial, and the finger pieces are high as required for mounting the same reliably on the stems. As a result, keyboards constructed in accordance with the prior art have a minimum height which cannot be further reduced.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of the prior art keyboards for business machines and provide a keyboard of simple construction consisting of key means which are connected with adjacent key means and are guided by the same.

Another object of the invention is to provide each key means with a support arm and a connecting arm, and guide each connecting arm by the b arm of an adjacent key means.

Another object of the invention is to form a keyboard of identical molded key means which are mounted on parallel shafts.

Another object of the invention is to provide a keyboard in which the finger pieces are located closely adjacent each other arranged in perpendicular lines and columns, and having top faces located in a common plane.

With these objects in view, an embodiment of the invention comprises a row of key means forming a vertical column of a keyboard. Each key means of a row includes a finger piece, a connecting arm, and a support arm. The support arm of each key means is located under the finger piece of the respective adjacent preceding key means of the row, and has guide means, preferably a rectangular opening, for guiding the connecting arm of the preceding key means which passes through the opening. A plurality of mounting means in the form of shafts, is provided for mounting the support arms of the key means of the row for angular movement, and each mounting shaft is located under a preceding key means, preferably under the finger piece of the preceding adjacent key means.

Since in accordance with the invention, the key means of each row overlap with and partly cover the following key means of the respective row, very low and compact keyboards are obtained by simple parts which can be easily assembled and operate almost without noise.

In the preferred embodiment of the invention, the support arm of each key has a forked end portion including two prongs having parallel edges which are spaced from each other a distance corresponding to the width of the connecting arm passing therethrough so that the same is guided during movement of the respective preceding adjacent key means, and form a straight row without requiring stationary additional bearings or guide means.

It is only necessary to fix the first or last key means of each row, whereupon all other key means of the same row are guided on each other and form a straight row which is perpendicular to the axes about which the key means turn. Since a plurality of rows is provided in the keyboard, corresponding key means of all rows form lines of key means in a direction parallel to the direction of the axes about which the key means turn between the normal and operative positions. Consequently, it is possible to use the same shaft for supporting all support arms of the key means of the same line. The position of the keyboard in a machine has no bearing on the arrangement of the invention.

In accordance with the invention, actuator portions of the connecting arms are used for operating movable elements, for example the resilient contact of a switch. It is advantageous to make the distance between the turning axis of a key and the actuator portion of the connecting arm greater than the distance between the axis and the finger piece, since a shorter manually effected stroke of the finger piece produces a greater effective stroke of the actuator portion and of the contact operated by the same.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a fragmentary plan view illustrating a keyboard in accordance with the invention;

FIG. 2 is a fragmentary sectional view taken on line II-II in FIG. 1;

FIG. 3 is a side view of a key; and

FIG. 4 is a bottom view of a key.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIGS. 2, 3 and 4, each key I has a finger piece 2 with a top face 2a, a support arm 3 projecting from the finger piece 2, and a connecting arm 4 projecting from the bottom of the finger piece and having at its free end. an actuator portion 4a cooperating with the resilient contact 7a of a switch 7. Connecting arm 4 has first and second stop portions 8 and 9 separated by a cutout.

As best seen in FIG. 4, the supporting arm 3 has a forked end portion including two prongs 3a whose confronting edges 3bbound opposite sides of opening 5. The connecting arm 4 has a width which is slightly less than the distance between the guide edges 3b.

Referring now to FIG. 1, the keyboard K of a business machine M comprises a plurality of lines L of key means 1 and a plurality of rows R of key means I which are perpendicular to each, other. A key 1a having a larger finger piece may be provided. Only the top faces 2a of the finger pieces 2 are visible in FIG. I.

FIG. 2 shows a single row R of key means 1. The supporting arm 3 of each key means 1 is mounted on a shaft 6 so that each key means 1 is movable between the illustrated normal position, and a angularly displaced lower operative position. Shafts 6 are spaced from each other the same distance, and each shaft 6 is used for supporting all key means I of a line L. The ends of shafts 6 are supported by supporting brackets I0 which are located on opposite sides of the keyboard K, and supported by the frame of the machine. As best seen in FIG. 4, the prongs 3a have aligned bearing bores 30 through which the respective shaft 6 passes so that a free shaft portion, not shown, located between the bearing bores 3c, crosses the opening 5 and closes the same.

The connecting arm 4 of each key means 1 passes through the opening 5 of the next lower successive key means of the same row R, and since connecting arm 4 fits into the opening 5 slidingly engaging the guide edges 3b, the supporting arm 3 of each key means guides the connecting arm 4 of the preceding adjacent higher key means 1.

Connecting arm 4 is located in the respective guide opening 5 in a position in which the stops 8 and 9 are located on opposite sides of the free shaft portion, not shown, crossing opening 5 and being located between the ends of prongs 3a. The respective shaft 6 abuts the inner face of stop 8 in the normal position of the key means due to the resilient force of the respective switch contact 7a acting on actuator end portion 4a of the respective connecting arm 4, so that the normal position of the key means 1, in which the top faces of the finger pieces 2 are located in a common plane, is determined by shaft 6. An additional spring, not shown, may be provided for urging each key means to the normal position.

When manual pressure is exerted on the top face 2a of the finger piece 2 of a key means I, the same turns in clockwise direction until the shaft of the following adjacent lower key means 1 abuts the inner face of stop portion 9. It will be noted that each shaft 6 and support arm 3 is located under the finger piece 1 of the preceding adjacent higher key means 1, while the actuator end portion 4a of the respective connecting arm is located under the finger piece 2 of the following adjacent lower key means 1.

As best seen in FIG. 3, connecting arm 4 projects at an obtuse angle from the bottom face of finger piece 2, and has such a length that it projects beyond the end of the finger piece. Since the distance between the bearing bores 30 in shaft 6 on the one hand, and actuator portion 4a on the other hand, is greater than the distance between the shaft 6 and the finger piece 2, a shorter manual stroke of the finger piece, determined by the width of the cutout between stops 8 and 9, will result in a larger stroke of the actuator end portion 4a of connecting arm 4, and consequently in a larger stroke of the movable contact element 7a, as required by the construction of switch 7. FIG. 3 shows in chain lines a differently positioned connecting arm 4 which does not offer this advantage.

FIG. 1 shows a finger piece 2' which is larger than the standard finger piece 2 and takes the place of key means omitted in an adjacent row.

Due to the fact that the guide means 3a, 3b of the support arms 3 guide the connecting arm 4 of the preceding adjacent key means, all key means of a row R are interconnected and form a straight row when all key means are in the normal position, as well as when one of the key means is depressed for operating the respective switch 7. Consequently, it is not necessary to provide stationary guide means for guiding the key means since lateral wobbling of the key means during movement to the operative position is prevented by the interengagement of the supporting and connecting arms of adjacent keys. All key means are identical, except special keys 2' having a larger finger piece, and can be manufactured by molding the entire key means as shown in FIGS. 3 and 4 as an integral piece of a synthetic plastic material. Evidently, the actuator portions 40 can be mechanically connected with movable elements of the machine, instead of operating switches 7.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of keyboards differing from the types described above.

While the invention has been illustrated and described as embodied in a row of interconnected keys guiding each other during movement to operative positions, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

lclaim:

1. Keyboard comprising a row of key means, each including a finger piece, a connecting arm, and a support arm, said support arm of each key means being located under said finger piece of the respective adjacent preceding key means of said row and having guide means for guiding said connecting arm of said preceding key means; and a plurality of mounting means for mounting said support arms of said key means for angular movement, respectively, and being located under a preceding key means, respectively.

2. Keyboard as claimed in claim 1 wherein said guide means is a portion of said supporting arm forming an opening through which said connecting arm of said preceding key means passes.

3. Keyboard as claimed in claim 2 wherein said portion of said support arm is formed with two parallel edges bounding said opening on opposite sides and being spaced from each other a distance corresponding to the width of the connecting arm passing therethrough for guiding the same during movement of the respective preceding key means so that said key means are guided and interconnected to form a straight row.

4. Keyboard as claimed in claim 3 wherein said portion of said support arm is a forked end portion including two prongs having said parallel edges; and wherein each mounting means includes a shaft passing through the free ends of said prongs and closing said opening.

5. Keyboard as claimed in claim 1 wherein said supporting arms of said key means have the same length; and wherein each mounting means includes a shaft passing through the free ends of said support arms, said shafts being parallel and spaced from each other the same distance so that said finger pieces are spaced said distance from each other in the direction of said row.

6. Keyboard as claimed in claim 5, comprising a plurality of parallel rows of key means having supporting arms and being parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; and wherein each of said shafts supports the supporting arms of all key means which are located in the same line for angular movement independently of each other.

7. Keyboard as claimed in claim 1 wherein each mounting means includes a shaft passing through the free end of the respective connecting arm; and wherein each connecting arm has two spaced stop portions located on opposite sides of the shaft supporting the respective adjacent successive key means of said row so that said first and second stop portions abut said shaft in two end positions of the respective key means.

8. Keyboard as claimed in claim 7 wherein said supporting arm has a forked end portion including two prongs having parallel edges bounding an opening, and being formed with aligned bearing bores; wherein said shaft passes through said aligned bearing bores and has a free shaft portion between said prongs crossing said opening and closing the same; wherein said first and second stop portions are located on opposite sides of said free shaft portion; wherein said connecting arm of said preceding key means passes through said opening; and wherein said edges constitute said guide means for said connecting arm.

9. Keyboard as claimed in claim 1 comprising a row of movable elements respectively located under the key means of said row; wherein said connecting arms of said key means have actuator end portions respectively cooperating with movable elements located under the respective following key means of said row of key means.

10. Keyboard as claimed in claim 9 wherein said movable elements are switches having a spring biased contact engaged and operated by said actuator portion in an operative position of the respective key means, and urging said key means resiliently into a normal position.

ll. Keyboard as claimed in claim 9 wherein the distance between each mounting means and the respective correlated finger piece along said supporting arm is less than the distance between each mounting means and said actuator portion of the respective connecting arm so that the stroke of said finger piece is less than the stroke of said actuator portion for operating said movable element.

12. Keyboard as claimed in claim 1 comprising a plurality of rows of key means parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; and wherein said finger pieces of selected adjacent key means are combined in at least one large finger piece.

13. Keyboard as claimed in claim 1 wherein said supporting arms of said key means have the same length; wherein each mounting means includes a shaft passing through the free ends of said support arms, said shafts being parallel and spaced from each other the-same distance so that said finger pieces are spaced said distance from each other in the direction of said row; comprising a plurality of parallel rows of key means having supporting arms and being parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; wherein each of said shafts supports the supporting arms of all key means which are located in the same line for angular movement independently of each other; and comprising a pair of supporting brackets located on opposite sides of said lines of key means, and supporting the ends of said shafts, respectively.

14. Keyboard as claimed in claim 13 wherein said brackets and shafts are located in a plane slanted to a horizontal plane; and wherein said finger pieces have top surfaces located in an other plane parallel to said plane.

15. Keyboard as claimed in claim 1 wherein each mounting means supports the end of said support arm of the respective key means, and is located under the finger piece of the respective adjacent preceding key means.

16. Keyboard as claimed in claim 1 wherein said support arm, said connecting arm, and said finger piece of each key means form an integral piece. 

1. Keyboard comprising a row of key means, each including a finger piece, a connecting arm, and a support arm, said support arm of each key means being located under said finger piece of the respective adjacent preceding key means of said row and having guide means for guiding said connecting arm of said preceding key means; and a plurality of mounting means for mounting said support arms of said key means for angular movement, respectively, and being located under a preceding key means, respectively.
 2. Keyboard as claimed in claim 1 wherein said guide means is a portion of said supporting arm forming an opening through which said connecting arm of said preceding key means passes.
 3. Keyboard as claimed in claim 2 wherein said portion of said support arm is formed with two parallel edges bounding said opening on opposite sides and being spaced from each other a distance corresponding to the width of the connecting arm passing therethrough for guiding the same during movement of the respective preceding key means so that said key means are guided and interconnected to form a straight row.
 4. Keyboard as claimed in claim 3 wherein said portion of said support arm is a forked end portion including two prongs having said parallel edges; and wherein each mounting means includes a shaft passing through the free ends of said prongs and closing said opening.
 5. Keyboard as claimed in claim 1 wherein said supporting arms of said key means have the same length; and wherein each mounting means includes a shaft passing through the free ends of said support arms, said shafts being parallel and spaced from each other the same distance so that said finger pieces are spaced said distance from each other in the direction of said row.
 6. Keyboard as claimed in claim 5, comprising a plurality of parallel rows of key means having supporting arms and being parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; and wherein each of said shafts supports the supporting arms of all key means which are located in the same line for angular movement independently of each other.
 7. Keyboard as claimed in claim 1 wherein each mounting means includes a shaft passing through the free end of the respective connecting arm; and wherein each connecting arm has two spaced stop portions located on opposite sides of the shaft supporting the respective adjacent successive key means of said row so that said first and second stop portions abut said shaft in two end positions of the respective key means.
 8. Keyboard as claimed in claim 7 wherein said supporting arm has a forked end portion including two prongs having parallel edges bounding an opening, and being formed with aligned bearing bores; wherein said shaft passes through said aligned Bearing bores and has a free shaft portion between said prongs crossing said opening and closing the same; wherein said first and second stop portions are located on opposite sides of said free shaft portion; wherein said connecting arm of said preceding key means passes through said opening; and wherein said edges constitute said guide means for said connecting arm.
 9. Keyboard as claimed in claim 1 comprising a row of movable elements respectively located under the key means of said row; wherein said connecting arms of said key means have actuator end portions respectively cooperating with movable elements located under the respective following key means of said row of key means.
 10. Keyboard as claimed in claim 9 wherein said movable elements are switches having a spring biased contact engaged and operated by said actuator portion in an operative position of the respective key means, and urging said key means resiliently into a normal position.
 11. Keyboard as claimed in claim 9 wherein the distance between each mounting means and the respective correlated finger piece along said supporting arm is less than the distance between each mounting means and said actuator portion of the respective connecting arm so that the stroke of said finger piece is less than the stroke of said actuator portion for operating said movable element.
 12. Keyboard as claimed in claim 1 comprising a plurality of rows of key means parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; and wherein said finger pieces of selected adjacent key means are combined in at least one large finger piece.
 13. Keyboard as claimed in claim 1 wherein said supporting arms of said key means have the same length; wherein each mounting means includes a shaft passing through the free ends of said support arms, said shafts being parallel and spaced from each other the same distance so that said finger pieces are spaced said distance from each other in the direction of said row; comprising a plurality of parallel rows of key means having supporting arms and being parallel with said row of key means so that the key means of all rows form lines of key means transverse to the direction of said rows; wherein each of said shafts supports the supporting arms of all key means which are located in the same line for angular movement independently of each other; and comprising a pair of supporting brackets located on opposite sides of said lines of key means, and supporting the ends of said shafts, respectively.
 14. Keyboard as claimed in claim 13 wherein said brackets and shafts are located in a plane slanted to a horizontal plane; and wherein said finger pieces have top surfaces located in an other plane parallel to said plane.
 15. Keyboard as claimed in claim 1 wherein each mounting means supports the end of said support arm of the respective key means, and is located under the finger piece of the respective adjacent preceding key means.
 16. Keyboard as claimed in claim 1 wherein said support arm, said connecting arm, and said finger piece of each key means form an integral piece. 